XML 74 R24.htm IDEA: XBRL DOCUMENT
v2.4.1.9

Risks and Uncertainties | 12 Months Ended
--- | ---
Dec. 31, 2014
Risks and Uncertainties [Abstract] |
Risks and Uncertainties | Risks and Uncertainties Many businesses are still experiencing the effects of uncertain conditions in the global economy and capital markets, reduced consumer spending and confidence, and continued volatility, which could adversely impact the Company’s financial condition, results of operations, and liquidity. Further, the volatility and disruptions in global capital markets could adversely affect the Company’s investment portfolio. Although the disruption in the global financial markets has moderated, not all global financial markets are functioning normally. The Company is unable to predict the impact of current and future global economic conditions on the United States, and California, where the majority of the Company’s business is produced. The Company applies the fair value option to its investment portfolio. Rapidly changing and unprecedented credit and equity market conditions could materially impact the valuation of securities as reported within the Company’s financial statements, and the period-to-period changes in value could vary significantly. Decreases in market value may have a material adverse effect on the Company’s financial condition or results of operations.

X
- Definition Risks And Uncertainties [Text Block] + References No definition available. + Details
Name: | mcy_RisksAndUncertaintiesTextBlock
Namespace Prefix: | mcy_
Data Type: | nonnum:textBlockItemType
Balance Type: | na
Period Type: | duration

X
- Details
Name: | us-gaap_RisksAndUncertaintiesAbstract
Namespace Prefix: | us-gaap_
Data Type: | xbrli:stringItemType
Balance Type: | na
Period Type: | duration